Singing in the rain at Copacabana

Without a doubt, the mood during Pope Francis' homecoming to Latin America has been mostly festive. For several hours Thursday afternoon, the area around Rio de Janeiro's famed Copacabana beach was dominated by the sounds of World Youth Day pilgrims chanting, shouting and singing, getting ready for their first real glimpse of Francis that night. They were joined by scores of ordinary Brazilians eager to join the party.

The weather, however, has been anything but upbeat. Rain, sometimes light and sometimes driving, has marred virtually every event on the schedule, often meaning that when Francis speaks, he's looking out over a sea of umbrellas.

The dreadful conditions also meant that Thursday night, throngs of high-octane Catholic youth spent much of the evening literally singing in the rain. Once Thursday's welcoming ceremony with the pope got underway, it too was composed largely of a series of song and dance numbers.

The rain has been a constant headache throughout the week, especially since most venues in Rio are designed for open-air crowds. The hottest-selling item among pilgrims and lookers-on at papal venues, aside from banners festooned with pictures of the pope, has been plastic ponchos to ward off the elements.

The pope joked about the weather Thursday in a welcoming session with a crowd estimated at around 1 million. He said he'd always heard that carioca, a Portuguese term for inhabitants of Rio de Janeiro, didn't like the rain and cold, but they proved tonight that "your faith is stronger."

"Congratulations: You're true witnesses," he told them.

Thursday, the weather forced three critical adjustments to the remaining schedule for World Youth Day:

• Friday night's youth vigil, originally scheduled for a field 30 miles outside the city called Guaratiba, has been moved to the Copacabana beach. Because of the rain, the originally planned area has been turned into a sea of mud.
• Youth have reportedly been advised not to camp out overnight, as is the custom during World Youth Days, but to return to wherever they're staying.
• The culminating Mass on Sunday, which is expected to draw between 1.5 million and 2 million people, will also be held on the beach.

When he arrived Thursday evening, Francis told the youth, "This week, Rio has become the center of the church, its heart both youthful and vibrant."

Before speaking, the pope made his way along the beachfront in the jeep he's been using throughout the trip, covered with an arc of plexiglass to keep him dry but otherwise open to the crowds. That allowed him to stop occasionally, as he likes to do, to kiss babies and chat with people on either side of his route.

At one point, someone passed him a cup containing maté, a traditional South American tea that's much loved by Argentinians. Francis took a long drink, then flashed a thumbs-up.

At the beginning of the event, Francis asked for a moment of silence to recall 21-year-old Sophie Moriniere, a member of a Paris World Youth Day pilgrim group who was killed July 17 in a road accident in French Guiana.

He also thanked Benedict XVI for initially extending the invitation to Rio de Janeiro and asked the crowd to offer the pope emeritus a round of applause.

Francis unrolled some of his trademark folksy wisdom Thursday in the context of urging young believers to "put on" the faith.

"What does this mean?" the pope asked. "When we prepare a plate of food and we see that it needs salt, well, we 'put on' salt; when it needs oil, then you 'put on' oil."

"And so it is in our life, dear young friends: If we want it to have real meaning and fulfillment, as you want and as you deserve, I say to each one of you, 'Put on faith,' and your life will take on a new flavor."

Turning to faith in Christ, the pope argued, produces a "Copernican revolution" -- no longer is one's self the center of existence, but rather, God.

Francis also returned to his favorite spiritual theme Thursday evening -- mercy.

"Do not be afraid to ask God's forgiveness," he said. "He never tires of forgiving us, like a father who loves us. God is pure mercy."

Francis urged the young people to be witnesses to Christ and the Gospel, thereby offering "a ray of his light" to the world.

Friday morning, Francis will hear confessions from five young people taking part in World Youth Day. He'll then meet five young people currently serving prison sentences before having lunch with a delegation of World Youth Day pilgrims at the archbishop's palace in Rio de Janeiro.

In the evening, the customary Via Crucis procession for World Youth Day will be staged in the streets of Rio, with Francis following the procession and taking part in the final stage.

On Saturday, Francis will say Mass with the bishops, priests and religious taking part in World Youth Day, meet members of the Brazilian government and have lunch with Brazilian bishops ahead of the evening's youth vigil.

(Follow John Allen on Twitter: @JohnLAllenJr)